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Dietary potassium-diformate affects growth performance and survival rates of vannamei-shrimp in hatchery and grow-out in worldwide aquaculture Christian Lßckstädt, ADDCON GmbH
Intensive production of the whiteleg shrimp, Litopenaeus vannamei (Boone 1931), in Central America and SE Asia is estimated to have almost reached 4.0 million tons (FAO, GOAL, 2019), thus showing strong signs of recovery in the last couple of years. Despite remarkable progress in shrimp nutrition and feed formulation during the past years, disease outbreaks in shrimp ponds can still lead to farming setbacks and increased use of antibiotics. Growing awareness from consumers and producers of aquaculture species, however, has driven demand for responsible and sustainable aquaculture. Regulatory authorities in most exporting countries now focus on the misuse of antibiotic growth promoters (AGP) in aquaculture, while public attention has shifted towards sustainable production methods. Alternative additives are being developed to replace the AGPs.
Acidifiers to replace AGPs Acidifiers are one of various alternatives spearheading environmentally friendly and nutritive-sustainable aquaculture approaches. Currently, the most widely tested organic acid molecule in aquaculture is potassium diformate (KDF). It has been tested and used successfully, among others, in salmon, trout, tilapia, Asian and European sea bass and pangasius. Its value to the shrimp production cycle has also been demonstrated in several field and research trials. Potassium diformate is a double-salt formic acid molecule which decreases gastrointestinal pH and thereby intensifies the release of buffering fluids, containing enzymes, from the hepatopancreas. Formate also diffuses into pathogenic bacteria inside the digestive tract and acidifies their metabolism, leading to bacterial cell death. Furthermore, beneficial bacteria (Lactobacilli, Bifidobacteria) are supported (eubiosis), which may lead to improved gut health, resulting in stronger condition of the shrimp. Acidifiers in vannamei PLs One of the most crucial periods in the life cycle of shrimp is the post-larval stage when shrimp feeding is changed from algae and brine shrimp nauplii to commercially formulated larval diets. Survival rates during this period are critical to later productivity. Pathogenic bacteria can dramatically increase mortality in the shrimp hatchery. Therefore, the use of potassium diformate was tested during this production stage (He et al., 2006). The group
Aquafeed: Advances in Processing & Formulation Vol 12 Issue 2 2020
